Can zakaah be given to one who suffers from kidney failure?

A person’s need for medical treatment is a real need, so if we find someone who needs medical treatment but does not have enough money to pay for treatment, there is nothing wrong with giving zakaah to him, because the aim of zakaah is to meet people’s needs. End quote. 

Majmoo’ Fataawa al-Shaykh Ibn ‘Uthaymeen (18/342). 

But if these sick people are well off and do not need the money, then it is not permissible to give zakaah to them. 

And Allaah knows best.